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141.
Sequence of a PAL-related lipoprotein from Bacillus subtilis 总被引:4,自引:0,他引:4
Harri Hemilä 《FEMS microbiology letters》1991,82(1):37-41
The sequence of a small Bacillus subtilis lipoprotein is reported. The gene encodes a protein of 124 amino acids, which shows a low but statistically significant homology to the peptidoglycan-associated lipoproteins (PAL) of Escherichia coli and Haemophilus influenzae. Although the functions of these proteins have not been confirmed, they are obviously structural proteins. In E. coli the gene for the peptidoglycan-associated lipoprotein appears to be essential. 相似文献
142.
H Korhonen M Harri 《Comparative biochemistry and physiology. A, Comparative physiology》1986,84(2):361-364
Infrared thermographs showed that heat loss of the raccoon dog (Nyctereutes procyonoides Gray 1834) is greatest from the chest, the head, the abdomen and the feet. The blue fox (Alopex lagopus) seems to be somewhat better insulated. Mass-0.75 specific heat transfer coefficients (W/kg 0.75 per degrees C) in both species were similar. The wooden nest was able to decrease it significantly. The results support the conclusion that heat loss, and thus the energy costs, of studied species could be reduced by providing them with either a winter nest or a rest-shelf in the cage. 相似文献
143.
Piia Karisola Maili Lehto Pia Kinaret Niina Ahonen Rita Haapakoski Minna Anthoni Masaru Taniguchi Henrik Wolff Anne Puustinen Harri Alenius 《PloS one》2015,10(6)
CD1d-restricted invariant natural killer T (iNKT) cells play a critical role in the induction of airway hyperreactivity (AHR). After intranasal alpha-galactosylceramide (α-GalCer) administration, bronchoalveolar lavage fluid (BALF) proteins from mouse lung were resolved by two-dimensional differential gel electrophoresis (2D-DIGE), and identified by tandem mass spectroscopy. A lack of iNKT cells prevented the development of airway responses including AHR, neutrophilia and the production of the proinflammatory cytokines in lungs. Differentially abundant proteins in the BALF proteome of α-GalCer-treated wild type mice included lungkine (CXCL15), pulmonary surfactant-associated protein D (SFTPD), calcium-activated chloride channel regulator 1 (CLCA1), fragments of complement 3, chitinase 3-like proteins 1 (CH3LI) and 3 (CH3L3) and neutrophil gelatinase-associated lipocalin (NGAL). These proteins may contribute to iNKT regulated AHR via several mechanisms: altering leukocyte chemotaxis, increasing airway mucus production and possibly via complement activation. 相似文献
144.
Jojanneke A. Bastiaansen Tarrant D. R. Cummins Harri?tte Riese Arie M. van Roon Ilja M. Nolte Albertine J. Oldehinkel Mark A. Bellgrove 《PloS one》2015,10(5)
The catecholamines dopamine and noradrenaline have been implicated in spontaneous low-frequency fluctuations in reaction time, which are associated with attention deficit hyperactivity disorder (ADHD) and subclinical attentional problems. The molecular genetic substrates of these behavioral phenotypes, which reflect frequency ranges of intrinsic neuronal oscillations (Slow-4: 0.027-0.073 Hz; Slow-5: 0.010-0.027 Hz), have not yet been investigated. In this study, we performed regression analyses with an additive model to examine associations between low-frequency fluctuations in reaction time during a sustained attention task and genetic markers across 23 autosomal catecholamine genes in a large young adult population cohort (n = 964), which yielded greater than 80% power to detect a small effect size (f2 = 0.02) and 100% power to detect a small/medium effect size (f2 = 0.15). At significance levels corrected for multiple comparisons, none of the gene variants were associated with the magnitude of low-frequency fluctuations. Given the study’s strong statistical power and dense coverage of the catecholamine genes, this either indicates that associations between low-frequency fluctuation measures and catecholamine gene variants are absent or that they are of very small effect size. Nominally significant associations were observed between variations in the alpha-2A adrenergic receptor gene (ADRA2A) and the Slow-5 band. This is in line with previous reports of an association between ADRA2A gene variants and general reaction time variability during response selection tasks, but the specific association of these gene variants and low-frequency fluctuations requires further confirmation. Pharmacological challenge studies could in the future provide convergent evidence for the noradrenergic modulation of both general and time sensitive measures of intra-individual variability in reaction time. 相似文献
145.
The raccoon dog (Nyctereutes procyonoides) is an introduced species in Europe with a continually expanding range. Since the species is capable of affecting local ecosystems and is a vector for a number of severe zoonotic diseases, it is important to understand its food habits. Raccoon dog diet was studied in Estonia by examining the contents of 223 stomach samples collected during the coldest period of the year, August to March, in 2010–2012. The most frequently consumed food categories were anthropogenic plants (e.g. cereals, fruits; FO = 56.1%) and carrion (e.g. carcasses of artiodactyls and carnivores; FO = 48.4%). Carrion was also the only food category that was consumed significantly more frequently by raccoon dogs exhibiting symptoms of sarcoptic mange than by uninfected animals. Small mammals, which represent intermediate hosts for the zoonotic tapeworm Echinococcus multilocularis, were more commonly recorded in samples also containing anthropogenic plants than expected by chance. Comparison of raccoon dog and red fox (Vulpes vulpes) diet in Estonia revealed higher overlap than found elsewhere in Europe, with ‘carrion’ and ‘anthropogenic plants’ making up the bulk of both species’ diet; however, raccoon dogs were more omnivorous than red foxes. Our results suggest that while the use of most food categories reflects the phenology of natural food sources, ‘anthropogenic plants’ and ‘carrion’ provide an essential resource for raccoon dogs during the coldest period of the year, with the latter resource especially important for individuals infected with sarcoptic mange. Since both of these food categories and small mammals are often found at supplementary feeding sites for wild boar (Sus scrofa), this game management practice may facilitate high densities of mesocarnivores and promote the spread of some severe zoonotic diseases, including alveolar echinococcosis, trichinellosis, rabies and sarcoptic mange. 相似文献
146.
Satu Mikkola Izabela Zagorowska Harri Lönnberg 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1267-1268
Abstract The Zn2+ promoted hydrolysis of phosphodiester bonds of RNA has been studied by using a series of model compounds from dinucleoside monophosphates to oligo- and polynucleotides. The results will be discussed with respect to complex formation between the metal ion catalysts and substrates. 相似文献
147.
Christina Orsmark Pietras Johanna Vendelin Francesca Anedda Sara Bruce Mikael Adner Lilli Sundman Ville Pulkkinen Harri Alenius Mauro D'Amato Cilla Söderhäll Juha Kere 《BMC pulmonary medicine》2011,11(1):39
Background
Neuropeptide S Receptor 1 (NPSR1, GPRA, GPR154) was first identified as an asthma candidate gene through positional cloning and has since been replicated as an asthma and allergy susceptibility gene in several independent association studies. In humans, NPSR1 encodes two G protein-coupled receptor variants, NPSR1-A and NPSR1-B, with unique intracellular C-termini. Both isoforms show distinct expression pattern in asthmatic airways. Although NPSR1-A has been extensively studied, functional differences and properties of NPSR1-B have not yet been clearly examined. Our objective was to investigate downstream signalling properties of NPSR1-B and functional differences between NPSR1-A and NPSR1-B.Methods
HEK-293 cells transiently overexpressing NPSR1-A or NPSR1-B were stimulated with the ligand neuropeptide S (NPS) and downstream signalling effects were monitored by genome-scale affymetrix expression-arrays. The results were verified by NPS concentration-response and time series analysis using qRT-PCR, cAMP and Ca2+ assays, and cAMP/PKA, MAPK/JNK and MAPK/ERK pathway specific reporter assays.Results
NPSR1-B signalled through the same pathways and regulated the same genes as NPSR1-A, but NPSR1-B yielded lower induction on effector genes than NPSR1-A, with one notable exception, CD69, a marker of regulatory T cells.Conclusions
We conclude that NPSR1-B is regulating essentially identical set of genes as NPSR1-A, with few, but possibly important exceptions, and that NPSR1-A induces stronger signalling effects than NPSR1-B. Our findings suggest an isoform-specific link to pathogenetic processes in asthma and allergy.148.
Pöllänen E Sipilä S Alen M Ronkainen PH Ankarberg-Lindgren C Puolakka J Suominen H Hämäläinen E Turpeinen U Konttinen YT Kovanen V 《Aging cell》2011,10(4):650-660
Aging is associated with gradual decline of skeletal muscle strength and mass often leading to diminished muscle quality. This phenomenon is known as sarcopenia and affects about 30% of the over 60-year-old population. Androgens act as anabolic agents regulating muscle mass and improving muscle performance. The role of female sex steroids as well as the ability of skeletal muscle tissue to locally produce sex steroids has been less extensively studied. We show that despite the extensive systemic deficit of sex steroid hormones in postmenopausal compared to premenopausal women, the hormone content of skeletal muscle does not follow the same trend. In contrast to the systemic levels, muscle tissue of post- and premenopausal women had similar concentrations of dehydroepiandrosterone and androstenedione, while the concentrations of estradiol and testosterone were significantly higher in muscle of the postmenopausal women. The presence of steroidogenetic enzymes in muscle tissue indicates that the elevated postmenopausal steroid levels in skeletal muscle are because of local steroidogenesis. The circulating sex steroids were associated with better muscle quality while the muscle concentrations reflected the amount of infiltrated fat within muscle tissue. We conclude that systemically delivered and peripherally produced sex steroids have distinct roles in the regulation of neuromuscular characteristics during aging. 相似文献
149.
Siikala E Bowyer P Richardson M Saxen H Sanglard D Rautemaa R 《FEMS yeast research》2011,11(6):494-498
Expression of the alcohol dehydrogenase gene ADH1, which converts ethanol into carcinogenic acetaldehyde, significantly inversely correlated with the expression of CDR1 and CDR2, genes linked to azole resistance in Candida albicans isolated from chronic oral candidosis in autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy (APECED, APS-I) patients. This is a novel link between candidal two-carbon metabolism genes and azole resistance. 相似文献